Db9 chord

The D-flat dominant ninth chord (abbreviated Db9 chord) is a five-note chord consisting of the notes D♭, F, A♭, C♭, and E♭. The chord is formed by adding a major ninth to the D-flat dominant seventh chord.

In practice, the fifth (A♭) is sometimes omitted from the Db9 chord because it's not always possible to play all notes simultaneously.